Replaceable ribbon cartridges adapted for use with computer printers, typewriters, and other types of printers are well-known in the art. Typically, such cartridges include a casing which houses an endless inked ribbon, together with a drive arrangement which is operated by the printer to move the ribbon along an endless path of travel and past a printing location which is outside of the casing and where the ribbon is engaged by the printing mechanism. The drive arrangement commonly comprises a rotatable drive roller, together with an idler or pinch roller which is spring biased against the drive roller to engage the ribbon which passes therebetween.
After a period of use of the cartridge, the ribbon's supply of ink becomes depleted, and the quality of the print deteriorates. To extend the life of the cartridge, it has been proposed to provide the cartridge with a re-inking capability. More particularly, in one prior design of this type, a porous ink filled roller is mounted in the casing so as to directly engage the ribbon drive roller, and during use, the drive roller transfers the ink to the ribbon. A design of this type is illustrated for example in U.S. Pat. No. 4,653,947. In another prior design, and as illustrated for example in U.S. Pat. Nos. 4,913,571 and 4,741,639, and Japanese Utility Model Publication No. 4-7155, a porous, ink filled roller is rotatably mounted in the casing, with the ink filled roller being in contact with a transfer roll which in turn engages the ribbon. The noted Japanese Utility Model also teaches that the ink filled roller may be moved laterally by the user to vary the contact pressure between the ink filled roller and the transfer roller, to thereby vary the rate of ink transfer.
The above prior designs are not, however, seen to be able to provide the user with a re-inking capability which may be significantly varied to meet applications having widely varying printing requirements. For example, the prior designs are not seen to be capable of permitting selective operation at a light transfer rate during the early life of the ribbon, and then shifting to a much heavier transfer rate when the print quality begins to deteriorate or when heavy ink transfer is required, such as in high speed printing operations or in the printing of graphics.
It is accordingly an advantage of the present invention that it provides a replaceable ribbon cartridge for printers and which has a user controllable re-inking capability which may be varied between a relatively light ink transfer rate, and a much heavier ink transfer rate.
It is a more particular advantage of the present invention that it provides a replaceable ribbon cartridge which incorporates a movable re-inking roller which is movable by the user between a neutral or inoperative position, a first operative position wherein the re-inking roller contacts a first ink transfer roller adapted for light ink transfer to the ribbon, and a second operative position wherein the re-inking roller contacts a second ink transfer roller adapted for heavy ink transfer to the ribbon.